The culmination of 29 Australian happiness surveys over 12 years by Melbourne's Deakin University has revealed if you live within the golden triangle you're more than likely to be happy. Source: Supplied

A loving partner, up to $100,000 of household income and a social activity that offers a sense of purpose is the new "golden triangle of happiness" according to Deakin University psychologist Professor Robert Cummins.

And being fat is no barrier.

Prof Cummins has taken aim at doctors and societal attitudes which push the idea that fat or obese people are unhappy.

Doctors should start thinking more about their patient's overall happiness instead of focusing solely on high blood pressure and cholesterol problems, he said.

The culmination of 29 surveys over 12 years of research has found that (apart from having a catastrophic medical condition) health is not part of the three elements that comprise the golden triangle.

"Health is one of the least important domains of our measurement and the reason is that because people adapt to amazingly difficult medical circumstances", Prof Cummins said.

"We have looked very carefully at the effect of body weight on mood/happiness and people who are overweight, and even mildly obese, they are OK. Their mood/happiness is under control.

"People normally gain weight as they get into middle age and get older and the physicians jump up and down and get red in the face about this because it is associated with high blood pressure and cholesterol.

"We're talking about something which I think is more important - which is how people feel about themselves and their lives.

"The mild levels of being overweight don't affect happiness/mood very much at all."

Prof Cummins identified those in Obese Class 2 or 3, who have a body mass index of 35 or more, as being the cut off point for happiness.

Anyone with a BMI under that will not have their weight impacting on their happiness.

So if you're 1.8m tall and 110kg, or 1.5m and 75kg, you're classified as obese but not so obese it will impinge on your happiness.

Beyond that point social exclusion and interference with day-to-day routines starts to have an effect on an individual's happiness, Prof Cummins said.

The culmination of 29 Australian happiness surveys over 12 years by Melbourne's Deakin University has revealed it doesn't matter where you live, whether your collar is white or blue or whether you've got kids or not - if you live within the golden triangle you're more than likely to have a permanent smile on your face.

Prof Cummins has also offered hope to Australia's ageing population by saying that life really does get better with age.

"People who are then the happiest of the golden triangle group are the elderly with no dreadful conditions like severe arthritis,'' he said.

"Happiness tends to rise beyond the age of 55 or 60. I'm not quite sure whether it is because the kids have left home or they're thinking about leaving their dreadful job."

Prof Cummins explained the three elements:

RELATIONSHIPS

"More important than money is having a good intimate relationship," he said.

"You only need one person to share your life and having that person is incredibly important. "People who haven't got someone to share their life in an intimate way - where you can share your troubles - are very vulnerable to the bad things that happen to them. This is extremely consistent across all of our surveys."

MONEY

"The magic number is $100,000 of gross household income. It's not that more money makes it better, it is that you need a certain amount," he said.

"How much you need depends on kids and your location.

"On a national average, mood/happiness rises with a gross household income up until that $100,000 point and then nothing further happens to it beyond that. Below that mood/happiness goes down.

"There is a myth that children decrease happiness. That is just not true.

"It depends on whether you've got financial resources and personal relationship resources and particularly if you're trying to raise four kids on $50,000, for example, where you're going to struggle."

ACTIVITY

"Having something interesting to do is the third element. People are happier if they are active; in a footy club, in a sewing circle, whatever," he said.

"If you can combine that activity with social contact and a sense of purpose then that is best.

"People who do volunteer work combine those very well. There more active they are and more socially connected the better they are.

"Chess clubs are not very good, for example, because they are not very socially interactive."

Prof Cummins, who is the brains behind the Australian Unity Wellbeing Index, has also pointed to an anomaly in international research: Australian widows are the world's happiest.

"The funny thing that happens in Australia - and it doesn't transfer to other countries - widows are really happy as a group," he said.

"Generally they are OK financially and it may well be they have got a new lease on life.

"It's a female thing rather than a male thing because females are so much better at creating socially supportive relationships than widowers are.

"It doesn't happen in other countries, most particularly in other countries where there is a massive and necessary financial hit when you're husband dies and you're left on your own to earn your own living."

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